In a tape drive, a tape is transported from a supply reel to a takeup reel along a tape path. Along the tape path, and between the reels, the tape is wrapped on a read/write head for recording and playback. In order to achieve very high track density data on a tape, lateral motion of the tape at the read/write head needs to be constrained. In other words, at the interface of the read/write head and the tape, it is undesirable to allow the tape to wander laterally from the desired tape path.
Another consideration in guiding the tape is the wrap angle and penetration of the read/write head. In order to achieve reliable recording and playback, the wrap angle and penetration at the read/write head needs to be properly aligned.
For addressing these problems, certain systems have used compliant tape guides to constrain the tape motion , but the compliant guides need to be very soft for thinner tapes, and resonance is difficult to eliminate. Other prior art systems use tapered or crowned rollers to control the tape motion, but the effects of these special shaped rollers become less efficient when thinner tape is used.
Other attempts at constraining the tape edges have used alternate edge guiding by fixed flanges. A concern with such solutions is the wearing of the tape edge by the fixed flanges. Another solution uses alternate edge guiding, but with flanged rollers. However, such an arrangement aligns two groups of rollers to two reference surfaces respectively. 